Lubricating oil additive



Patented Aug. 5, 1952 UNITED STATES PATENT OFFICE 2,606,182 LUBRICATINGOIL ADDITIYE John M. Musselman, South Euclid, Ohio, assignor to TheStandard Oil Company, Cleveland, Ohio,

a corporation of Ohio No Drawing. Application June '1, 1947,

. Serial No. 753,359

in an internal combustion engine operating at high temperatures andinwhich the lubricant is in close contact with metallic surfaces, metalcompounds and high temperature gases. They are also suitable as extremepressure lubricants in oils and greases.

The art appreciates that many diverse factors are involved in attaininga single lubricating oil addition agent which imparts to the oil littleor no lacquer formation and also shows little or no deterioration orcorrosion of metals, especially bearing metals with which the lubricantcomes in contact, as well as low oxidative deterioration, as indicatedby low viscosity increase, sludge, etc. It is very difiicult to producea single addi tion agent which is nearly optimum for all these factors,especially at a commercially interesting cost.

In accordance with the invention, it has been found that a reactionproduct may be obtained by reacting together an unsaturated hydrocarbon,an oxygen-containing organic compound and a phosphorus sulfide; and thisreaction product is an excellent lubricant or additive for lubricants.These reaction products have good solubility in oils and greases, andimprove the corrosion, lacquer, sludge, viscosity increase, and

the like characteristics thereof. They also improve the extreme pressurelubricating characteristics of oils and greases. Derivatives obtainedfrom these reaction products, e. g., metal derivatives, nitrogenbasederivativ'es, ester derivatives, or mixtures, or mixed derivativesthereof also have these desired properties. These products have improvedcorrosioncharacteristics as compared with the phosphorus sulfide-organicoxygen compound type additives, and also do not have the poor lacquercharacteristics of the phosphorus sulfide-olefin type additives.

The reaction products of the invention are to be distinguished from amixture of the sulfideclefin reaction product and the sulfide-organicoxygen-containing compound reaction product, and are superior to such amixture. This suggests that the reaction product of the invention is notsimplya mixture of the two types of reaction products, but rather thatthere is some interaction giving an unexpectedly superior prod uct.

cent is especially, desirable.

2 The objects achieved in accordance with the invention include theprovision of an agent which may be useful itself as a lubricant, andwhich when added to lubricants will markedly inhibit the veryobjectionable deposition-of lacquer, and,

at the sametime, inhibit acid and sludge formation, cor'rosionand othertypes of deterioration occurring under operating conditions; theprovision of lubricating oils containing such an addition agent; andother objects which will be apparent as embodiments of the invention aredisclosed hereinafter.

The reaction product may be made with direct admixture of the reactants,or, if desired, by

their admixture inthe presence of a diluent which may or may not besubsequently removed. A heavy oil such as white oil, or a lubricatingoil having about the same properties as that to which the newcomposition is to be added may be used as a diluent. The reaction isusually complete in about 10 hours or less time, generally 1 to 2 hours.The reaction time is a function of the temperature, the amount of thesulfide that is to react, the subdivision of the reactants, the

efficiency of mixing, etc.

The mixture of unsaturated hydrocarbon and oxygen-containing organiccompound may be reacted with the phosphorus sulfide or a mixture ofphosphorus sulfides in ratios from 5 to about .60 weight percent of thephosphorus sulfide based on the weight of the above mixture. Generallyabout to about 50 percent is the usual range that will be used,depending on the molecular weight of the unsaturated hydrocarbon and itsproportions relative to the oxygen-containing organic compound, andabout to about per- Small amounts show a significant improvement, andeconomic factors may make it undesirable to use more than is necessaryto achieve the desired improvement.

Phosphoruspentasulfide is preferred although other phosphorussulfides ormixtures of sulfides may be employed. Phosphoruspentasulfide is mosteconomic and readily available and for this reason is used in theillustrative examples.

In general, unsaturated hydrocarbons having atleast about 4- to 6 carbonatoms in the molecule are suitable. The unsaturated hydrocarbon maycontain one or more pairs of double or triple bonded carbon atoms.Olefihs are preferred including the high molecular weight olefinpolymers. These olefin polymers may be prepared by the polymerizationoflow molecular weight olefins, as is known to the art; Their molecularweight generally ranges above 1 and such polymers are known which have amoleculagagsaight in the rangeof about 3,000 to about 5 The advantagesof the invention are particularly apparent in the case-of productsobtained from unsaturated hydrocarbons having from about 6 to aboutcarbon atoms in the molecule. A commercially desirable olefin issocalled motor polymer or reduced motor polymer. C3 and C4 olefins bynon-selective polymerization, e. g., with a phosphorus acid typecatalyst. to 500 F., with a major portion boiling in the range of 120 to400 F.

A polymer gasoline fraction may be removed Motor polymer is usually madefrom Motor polymer boils in the range of 80 therefrom by fractionaldistillation to the 250 F. cut point, and this reduced form motorpolymer'is particularly useful. The reduced motor polymer may containsmall amounts of materials lighter thanthe trimer. Its average molecularweight is'about 145 and it preferably contains amajor amount of branchedchain olefins boiling below .600 F. The unsaturated hydrocarbon usedshould be selected, e. g., of a suitable molecular weight, to give afinal product having the desired oil solubility or dispersibility. It ispreferred to employ unsaturated .compounds which are soluble ordispersible in lubricating oil. Polyolefins may ;be used, but conjugatedpolyolefins giving an undue amount of sludge would not be preferred.

The oxygen-containing organic compound may contain hydroxy, carbonyl, orether oxygen; and is desirably of rather high molecular weight;preferably boiling above the reaction temperature; the reaction may beconducted under pres sure, if desired, in the case of lower boilingmaterials. Theremay be used ester waxes, as lanolin, degras, sperm oil;esters, as alkyl or cycloparaflin or aryl esters of organic acids; fattyoils, higher alcohols, higher carboxylic acids, saturated andunsaturated, monobasic and dibasic, petroleum acids, naphthenic acid,rosin, modified rosin, glycol ethers, higher ketones and aldehydes; alsohalogenated derivatives of any of these. Illustrative of someconveniently applicable materials are: beeswax, lanolin, sperm oil,other waxes, butyl stearate, ethyl lactate, methyl oleate, butylricinoleate, butyl phthalate, methyl stearate, methyl dichlorostearate,methyl chloronaphthenate, dichloropalmitic, acid, cocoanut oil, babassuoil, hydrogenated cocoanut and other vegetable oils, other fatty oils,ethylene glycol mono ethers, diglycol chlorohydrin, lauryl alcohol,stearic acid, lauric acid, oleic acid, palmitic acid, myristic acid,naphthalic acid, naphthoic acid, benzoic acid, naphthenic acids,hydroxystearic acid, dihydroxybenzoic acids, hydroxynaphthenic acids,dihydroxystearic acid, chlorobenzoic acid, dichlorostearic acids,dichlorobenzoic acid, dichlorodihydroxystearic acid, lactones,palmitone, oxidized petroleum fatty acid or other petroleum product, asoxidized wax, kerosene, gas oil or other oxidized petroleum oil. Theoxygenated compound used in forming the reaction product should beselected with reference to the use of the final composition and theproperties desired in it, e. g., to give a reaction product having oilsolubility or dispersibility.

The relative amounts of the unsaturated hydrocarbon and the oxygenatedorganic compound are not critical. Widely different proportions showsignificant improvement. Substantially equal weight ratios of thehydrocarbon and the oxygenated compound are suitable and proportions inthe range of 10 to 70 partsof the oxygenated compound to 90 to parts ofthe unsaturated hydrocarbon are preferred.

The reaction may be carried out in the presence or absence of air, or inthe atmosphere of inert or nondeleterious 'gas, such as nitrogen or H25.It may also be carried out under pressure, e. g., the pressure generatedwhen the reaction is carried out in a closed vessel.

A reaction temperature varies with unsaturated compound andoxygen-containing compound and, is readily ascertained. The optimum isin the range of 200 to 500 F., although a higher temperature which isbelow that at which the reaction product would be decomposed could beused. A temperature of at least 250 to 300 F. is preferred in manycases.

The final reaction mass is preferably centrifuged or filtered to removethe-by-product sludge, or other insoluble material. Any excess of avolatile reactant, or a volatile diluent, may be removed bydistillation. If desired, the final product may be solvent extractedwith a suitable solvent, e. g., liquid propane or isopropyl alcohol, orcontacted with an adsorbent such as activated charcoal, silica gel,activated clay, and the like.

An element of the sulfur family, i. e., sulfur, selenium or tellurium,can be incorporated into the reaction product. This sulfur can beincorporated by adding elemental sulfur or a compound which yieldssulfur, such as by treating the sulfide-derived reaction producttherewith, or treating a derivative of the sulfide-derived reactionproduct therewith.

If additional reacted sulfur is to be present in the additive, about0.01 to 2.0 and preferably 0.1 to 1.0 gram atoms of sulfur per mol ofthe phosphorus sulfide used, is incorporated by adding elemental sulfur,e. g., simultaneously with, or after the formation and cooling of theprimary reaction product; if after, the mass is maintained at about 200to 300 F. for about a few minutes to several hours, and preferably aboutone hour. Selenium'and tellurium function in much the same Way as sulfurin this respect, and may be incorporated similarly. Alternatively, thesulfur can be added to the metal, nitrogen base, or ester derivatives.

The sulfide, derived reaction products including those containing anadded sulfur family element may be utilized in the form of their metal,nitrogen base or ester derivatives. Mixed derivatives or mixtures of thederivatives may be employed. These derivatives are formed from agentscapable of replacingan acid hydrogen atom. Although the formation of theabove derivatives may not involve replacement of acid hydrogen, thematerials used as agents fall into the class of materials capable ofreplacing or reacting with acid hydrogen.

The metal derivatives may be formed from one or more metal compounds,such as their sulfides, oxides, hydroxides, carbides and cyanamides. Thepreferred metals are group I, group II and group III metals oftheperiodic table, such as potassium, zinc, barium and aluminum. Forparticular services, the heavier metals have particular use, i. e.,those below zinc in the electromotive series, such as chromium, cadmium,tin, lead, antimony, bismuth, arsenic, and the like. Y

The metal additive compounds, especially those fully saponified so as tohave a high metal content, may be mixed with oils to .form greases, withor without conventional soaps, and in such cases the metal additivecompounds serve. to

thicken the oil as well as to "stabilize it and impart a detergentaction.

When a metal, nitrogen base, or ester derivative containing subsequentlyadded reacted sulfur is desired, there are two primary alternative waysof producing it: (1) the sulfide-derived reaction product can be reactedwith an element of the sulfur family and this reaction product thenconverted into thederivative, or (2) the primary sulfide-derivedreaction product can be converted into the derivative and thisderivative then'reacted with an element of the'sulfur family.

In the preparation of the above type metal derivatives, the reactionstep of forming the metal derivatives may be carried out at temperaturesin the range of about 100 to about 350 F., a temperature in the range ofabout 180 to 250 F. being preferred.

From about 0.25 to about 6.0 equivalents of the metal compound may beused for mol'of the sulfide used in the sulfidederived reaction product,preferably about 1.0 to about 3.0 equivalents. An equivalent is thequotient of amol divided by the valence of the metal concerned.

The sulfide-derived reaction products may "be converted to theirnitrogen base derivatives by reaction with one or more basic nitrogenouscompounds, such as ammonia, amines, or heterocyclic nitrogen bases.Generally, ammonia and the gaseous or liquid amines or nitrogenousorganic compounds are preferred. Analogous polyamines may be usedsimilarly.

From about 0.25 to about 6.0 equivalents of the nitrogen base may beusedper mol of the sulfide in the sulfide-derived reaction product,preferably about 1 to about 4 equivalents. An equivalent is the quotientvalenceof the nitrogen base concerned.

of a mol divided by the The ester derivatives may be prepared reactionof the sulfide-derived reaction products 'with one or more alcohols, orthio-alcohols, or alkyl, aryl, cycloalkyl,

and heterocyclic compounds containing an alcoholic or thio-alcoholicgroup. The term ester derivative is used in its generic sense to includeany .oith'e above types of compounds. I

The reaction of forming the ester derivatives may be-carried out attemperatures in about the range of 100 to 350 F., a temperature of 180to 280 F. beingpreferred. Fromabout 0.2 to about 6.0 equivalents of theesterifying agent may be used per mol of the sulfide in thesulfide-derived reaction product, preferably about 1.0 to about 4.0equivalents. An equivalentis the quotient of a mol divided by thevalence (e. g., number of alcoholic or thiolgroups in the molecule) ofthe agent used.

It is beneficial to have water present in the reaction step of formingthe metal or the nitrogen base derivative, and this may be introduced aswater of crystallization, or as a hydrate of the metal compound or'ofthe nitrogen base, or it may be introduced separately.

A plurality of metals or of nitrogen bases, or of esterifying agents, ormixtures of any two-or more thereof, may be used.

If the amount of the metal, nitrogen base or alcohol or combinationsthereof, is small, the final product may be a mixture of the initialreaction product and the metal, nitrogen base or ester derivative.

The yields in the above reaction steps are very high. v

' The amountoi the final-reaction product (i. e., the additive) to beincorporated in an oil or 0 grease will depend upon the charact'eristicsof the oil orgrease and the intended-use. Some oils have more of atendency to corrode me'tals,

or to'form acids, sludges andla'cquer deposits than others, and suchoils require larger quantities of the addition agent. Also, oils thatare intended for higher temperatures require larger amounts of theadditive. In general, the range is from about '1 toabout- 10%; undersome circumstances, amoun't'sas low as-about 0.01% show a significantimprovement. since the secondary reaction product is a lubricant, thereis no upper limit. However, it maybe uneconomical to include in thelubricant more of the se'condary reaction product than is necessary to"impart the desired properties, such as 50%.

The following working examples illustrate the scope of the invention:

A GQNVENTIONAL'PETROLEUM BASE LUBRICATING. 01L

CONTAINING '1 TO 10% on ANY ONE or THE For.- LOWING COMPOSITIONS (ALLPARTS 0R PERCENTAGES A-RE BY WEIGHT UNLESS OTHERWISE INDICATED HEREIN1 1. Reaction product of 1 to 3 parts of cycle-- hexanol, 1 to 3 partsof reduced motor polymer, and 1 to 5 parts of P2S5 reacted together at'atemperature in the range of 200 to 500 'F.

2. Reaction product of 1110 3 parts of a glycerol stearate, 1 to '3parts ofcetenel, and l-to '5 parts of PzSs reacted-together at atemperature in the range of 200 to 500F.

3. Reaction product ofi to 3-parts iof degras, 1 to 3 parts of octene-Z,and 1 to 5 parts of P285 reacted together at a temperature in the rangeof 200 to 500 F. r r

4. Reaction productof "1 'to 3 parts of cetyl-alcohol, 1 to 3 parts ofpenta-decene-Biand.l to 5 parts of P235 reacted together at atemperature in the range of 200 to 500 F.

.Re'action product of 1 to 3 parts of coconut oil, 1 to 3 parts of motorpolymer, and 1'to 5 parts of P487 reacted together a't-a temperature inthe range of 200? to 500F.

6. Reaction product of 1 to 3 parts of natural beeswax,i1 to 3 parts ofreduced motor polymer,

and 1 to 5 parts of 'P'zssreactedtogether at a temperature in the rangeof 200 to 500 F.

'7'. Reaction product of 1 to3 parts of palmitonje, 1 to 3 parts ofhighly cracked hydrocarbon stock, and 1 to 5 parts of PzSs reactedtogether at a temperature in the rangeaof to 500 F.

8. Reaction product'of 1 to 3 parts of sperm oil,

1 to 3 parts of a mixture of C6 to C12 monoolefins, and 1 to 5 parts ofP zss reacted together at a ten'iperature in the range of .200?- to 500F. 1

9. Reaction product of 1 to -.3 -parts of diamyl phenol, 1 to 3 parts ofmotor lpolymenand 1 to 5 parts of P285 reacted together at a temperaturein the range of 200to400" F.

10. Reaction product of Ito-3 parts of amixture of stearic and oleicacid, .1 to 3 parts of a mixture of C8 to C1 mono-olefins, 1 to 5 partsof P285 reacted together at a temperature in the range of 200 to 500F.

11. Reaction product of- 1 to '3- partsv of methyl stearate, 1 to3*p'arts of highly-cracked'hydrm carbon stock,'and 1 5 partsof-PQS5reacted together at a temperature'in the range of"100 12. Reactionproduct of 1 to 3 parts of cyclohexanone. 1 to 3 parts of a mixture *of'G6 to GL2 V mono-olefins, andl "to-"5 pa rtsgof Pzs sreacted together at"a temperature in the range lof" 200 to 500 F.

Example A 38 parts of P285 is mixed with 100 parts of reduced motorpolymer and agitated for 8 hours at 350 F. in a pressure reactionvessel, at a pressure of about 100 pounds per square inch. Some gas isvented during the reaction, depending upon the free space in the vessel,in order to maintain this pressure. A 100% yield is obtained, based onthe motor polymer, and no sludge is formed, but it is preferred tofilter the reaction product. The product analyses 23.0% P, and 7.0% S;and is referred to as additive A hereinafter.

' Example B Hydrogenated sperm oil is available under the trade name ofSpermofol No. 52. It has an iodine value of 6-7, a melting point of50-52 C., a free fatty acid content (as oleic) of 1.0-2.0%, asaponification value of 135-138, and about 36% of unsaponifiables.

This hydrogenated sperm oil is reacted with 32% by weight of phosphorussulfide at a temperature of about 300 F. After the reaction is complete,which, under reaction conditions, takes one hour, the material ispermitted to stand, after which the by-product residue settles and thereaction product is decanted; following this, it is filtered with theuse of a filter aid. An 80% yield is obtained of the product; whichanalyses 2% P and 14% S; and this is referred to as additive Bhereinafter.

Example I (a) Following the'procedure of Example A, 32 parts ofphosphorus pentasulfide is reacted at 300 F. with a mixture of 50 partsof reduced motor polymer and 50 parts of the above describedhydrogenated sperm oil. An 86% yield of the product is obtained, afterfiltration to remove sludge, and it analyzes 5.57% P and 16.32% S; thisis referred to as additive 1(a) hereinafter.

Example I (b) A reaction product prepared in accordance with the aboveprocedure 1(a) is mixed with 11% by weight of potassium hydroxide and15% by weight of water, and the mixture heated with agitation at 300 F.for 30 minutes. The reaction mass is then blown with air whilemaintained at about 200 F. for 1% hours. It is then filtered hot. Thefiltered product analyzes 20.49% ash (as sulfate), 5.32% P-and 14.57% S;and is referred to hereinafter as additive I(b).

Example 1(0) A reaction product prepared in accordance with the aboveprocedure I(a) is mixed with 20% by weight of barium hydroxideoctahydrate and heated with agitation at 180 F. for 4 hours, and then at250 F. for 1 hour. The reaction mass is then blown with air whilemaintainedat 200 F. for l hours. It is then filtered hot. The filtrateproduct analyzes. 11.4% ash and 12.92% S and is' referred tohereinafter'as additiveI(c).

8 Examplev II (a) Following the procedure of Example 1(a), except using25 parts of phosphorus pentasulfide, a reaction product is prepared. A96% yield of a product is obtained, after filtration to remove sludge;it analyzes,3.68% P, and 13.78% S, and is referred to as additive II(a)hereinafter.

Example II (b) Following the procedure of Example 1(a), except using 40parts phosphorus pentasulfide, a reaction product is prepared. An 85%yield of of a product is obtained, after filtration to remove sludge; itanalyzes 5.8% P and 20.47% S, and is referred to as additive II(b)hereinafter.

Example III Following the procedure of Example 1(a), 34.75 parts ofphosphorus pentasulfide is reacted with a mixture of parts of reducedmotor polymer and 25 parts of the hydrogenated sperm oil. A 93.43% yieldof the product is obtained, after filtration to remove sludge; itanalyzes 6.72% P, and 18.14% S; and is referred to as additive IIIhereinafter.

Example IV Following the procedure of Example 1(a), 28.75 parts ofphosphorus pentasulfide is reacted with a mixture of 25 parts of reducedmotor polymer and 75 parts of the hydrogenated sperm oil. An 86% yieldof the product is obtained, after filtration to remove sludge; itanalyzes 3.61% P, and 15.05% S, and is referred to as additive IVhereinafter.

Example V Following the procedure of Example 1(a), 32 parts ofphosphorus pentasulfide is reacted at 250 F. with a mixture of 50 partsof reduced motor polymer and 50 parts of the above describedhydrogenated sperm oil. An 82.5% yield of the product is obtained, afterfiltration to remove sludge; it analyzes 6.64% P, and 16.46% S, and isreferred to as additive V hereinafter.

Example VI Following the procedure of Example 1(a), 32

parts of phosphorus pentasulfide is reacted at 350 F. with a mixture of50 parts of reduced motor polymer and 50 parts of the above describedhydrogenated sperm oil. An 87.27% yield of the product is obtained,after filtration to remove sludge; it analyzes 4.4% P, and 17.15% S, andis referred to as additive VI hereinafter.

Example VII Following the procedure of Example 1(a), 42 parts ofphosphorus pentasulfide is reacted at 300 F. with a mixture of 50 partsof reduced motor polymer and 50 parts of stearic acid. The product isfiltered to remove sludge, and it is referred to as additive VIIhereinafter.

Example VIII parts of phosphorus pentasulfide is reacted at 300 F. withamixtureof 50 partsofreduced motor polymer and 50 parts of. laurylalcohol;

and the product is referred to as additive IX hereinafter. 7

xample. X

Following the procedure of Example VII, 38 parts of phosphoruspentasulfide is reacted at 300 F. with a mixture of 50 parts of reducedmotor polymer and 50 parts of n-octyl alcohol,

and the product is referred to as additive X hereinafter.

Example. XI

Example XII.

Following the procedure of Example VII, 32 parts of phosphoruspentasulfide is reacted at 300 F. with a mixture of 50 parts of reducedmotor polymer and 50 parts of an oxidation product, obtained by thecontrolled oxidation of a fraction of Pennsylvania petroleum, of Sp. gr.at 158 F. 08654-08448 Viscosity, Saybolt sec. 1 40-49 Melting point, F.94-100 10- called degras. The product is filtered to remove sludge, andis referred to as additive XV hereinafter.

In testing the oils containing addition agents, an ethyl motor is used,under the following conditions:

Procedurenrfil 1 II Type engine Series ethyl Engine speed 1200 R. P. M.Sump temp 300 F. Jacket temp 212 F. Air fuel ratio 12-515 to 1Compression 7 to 1 Catalyst None For comparative purposes, the testvalues for piston skirt, acid number, pentane insolubles, and 1/100 theviscosity increase maybe added; the sum is multiplied by 10, and dividedby the number of hours the test is run. The resulting value is termedthe demerit rating.

A conventional solvent extracted lubricating oil base stock SAE 30) andblended compositions of this oil made in accordance with the inventionwere submitted to tests in accordance with the described ethyl motorprocedure. The results in the following Tables A, B and C are typical.

TABLE A (50-hour 80-hour IOU-hour Additive of Example No. and O A 1 v hn 0.5%A 1.0% 0.5%A 1.0% narrates.rarer. m 0 w 1 0 m a Piston SkirtRating..." 2.5 0.5 4.0 1.0 5.0 2.5 Viscosity Increase (SUS) 131 59 15561 167 63 Acid Number 0.875 0.75 0.875 1.0 1.0 1. 25 Ientane Insolubles(in percent by weig 1.0 0. 2 1.0 0. 4 1.8 0.5 Dernerit Rating 0.93 0.350. 94. 0.38 0.95 0.49 Corrosion of Cu-Pb bearing metal (in mgms. weightlcs per bearinghalf-she11) 1 286 85.0

Flash point F. 280-300 The oil alone only ran 20 hours, and showed aAcid No, 8-12 demerit, rating of 6.7. Saponification No 100-140 ThisIalole A data shows the marked supe- (and available commercially as Alex152).

The reaction product is filtered to remove sludge;

and is referred to as additive XII hereinafter.

Example XIII Following the procedure of Example VII, 32 parts ofphosphorus pentasulfide is reacted at 300 F. with a mixture of parts ofreduced motor polymer and 50 parts of commercial diamylphenol; and theproduct is referred to as additive XIII hereinafter.

Exagnple XIV Example XV Following the procedure of Example VII, 33 partsof phosphorus pentasulfide is reacted at 300 F. with a mixture of 50parts of reduced motor polymer and 50 parts of the crude grease obtainedby washing sheeps wool, sometimes riority of solvent extracted baselubricating oil containing-the additive 1(a) of the invention, ascompared to the same 011 containing about the same total amount of theseparately reacted materials A and B (the latter may be regarded as thesum of the effects of the two added agents). The more than 3-foldimprovement in corrosion together with the about 2-fold improvement indemerit rating is. especially noteworthy. I

In addition, it may be stated that the oil containing 1% of additive Aalone showed a piston skirt rating of 5 .0 at 60 hours (i. e., lacquercharacteristic poorer) and the oil containing 1% of additive B, aloneshowed a corrosion of 507. at hours (i. e. corrosion characteristicpoorer).

TABLE B. -11 15) The above data show that the metal derivative additivesI(b) and 1(0) are advantageous, especially as to piston skirt rating.The additives 11 prepared from a different ratio of P285, II(a) (25%P285) and 11(2)) (40% P2S5) also are advantageous; the latter shows thebetter piston skirt rating of the two.

TABLE (100-hours) 1% by Weight of Additive of Example N0 I (a) III IV VVI Piston Skirt Rating 2. 2. 5 2 5 3.0 2. 5 Viscosity Increase (SUS) 6391 65 52 147 Acid Number 1. 1. 75 1.25 1. 0 1.0 Pentane Insolubles (inpercent by weight) 0.5 0.7 0. 4 0.75 0. 5 Demerit Rating 0.49 0. 60 0.48 0.63 0.55 Corrosion of Ou-Pb bearing metal (in mgms. weight loss perbearing half-shell) 90. 3 44. 0 312 90. 0

The above data show that additives prepared from unequal weight ratiosof unsaturated hydrocarbon to oxygenated-compound also are advantageous;the additive IV (from 3 to 1 mixture of the hydrogenated sperm oil tothe reduced motor polymer) shows especially low corrosion. The additivesprepared at different preferred reaction temperatures are advantageous.The additive 1(a) (prepared at 300 F.) and the additive VI (prepared at350 F.) are more advantageous than that prepared at 250 F. (i. e., V).This data indicates that a reaction temperature of at least about 275 F.(or a subsequent heating of the reaction product to such a temperature)is to be preferred where the more advantageous product is desired.

The Sohio corrosion test was used in evaluating other blends made inaccordance with the invention. This test is described in a co-pendingapplication of E. C. Hughes, J. D. Bartleson, M. S. Sunday and M. M.Fink, which also correlates the results of the laboratory tests with aChevrolet engine test.

Essentially the laboratory test equipment consists of a verticalthermostatically heated glass test tube (45 mm. outside diameter and 42cm. long) into which is placed the corrosion test unit. An air inlet isprovided for admitting air into the lower end of the corrosion unit insuch a way that in rising the air will cause the oil and suspendedmaterial therein to circulate into the corrosion unit. The tube isfilled with an amount of the oil to be tested which is at leastsufilcient to submerge the metals being tested.

The corrosion test unit essentially consists in a circular relativelyfine grained copper-lead test piece of lg" O. D., which has a 4 diameterhole in its center (i. e., shaped like an ordinary washer). The testpiece has an exposed copperlead surface of 3.00 sq. cm. Of this surfacearea, 1.85 sq. cm. acts as a loaded bearing, and is contacted by a partof the cylindrical surface of a hardened steel drill rod 4" diameter andl" long, and of 51-57 Rockwell hardness).

The drill rod is held in a special holder, and the holder is rotated sothat the surface of the drill rod which contacts the bearing sweeps thebearing surface (the drill rod is not rotated on its own axis and thesurface of the drill rod which contacts the bearing is not changed).

The corrosion test unit means for holding the bearing and the drill rodis a steel tubing (15" long and 15 O. D.) which is attached to asupport. A steel cup (1" long, 13%" 0. D. by l? I. D.) is threaded intothe steel tube, at the lower end. The cup has a diameter hole in thebottom for admitting the oil into the corrosion chamber. The copper-leadtest piece fits snugly into the steel cup and the hole in the test piecefits over the hole in the steel cup. A section of steel rod in diameterand 19 long) serves as a shaft and is positioned by 2 bearings which arefixedly set in the'outer steel tubing, one near the top and one near thelower (threaded) end thereof. Several holes are drilled just above andjust below the lower hearing. The holesabove the bearing facilitatecleaning the apparatus, while the holes below the bearing enable thecirculation of oil through the corrosion chamber. The drill rod holderis connected to the shaft by a self-aligning yoke and pin coupling. Thisassures instantaneous and continuous alignment of the drill rod bearingmember against the bearing surface at all times. A pulley is fitted tothe top of the steel shaft and the shaft is connected therethrough to apower source. The shaft is rotated at about 6'75 R; P. M. and the weightof the shaft and attached members is about 600 grams, which is thegravitational force which represents the thrust on the bearing. The airlift from the air inlet pumps the oil through the chamber containing thetest piece and out through the holes in the steel tubing.

The ratios of surface active metals to the volume of oil in an internalcombustion test engine are nearly quantitatively duplicated in the testequipment. The temperature used is approximately that of the bearingsurface. The rate of air flow per volume of oil is adjusted to the sameas the average for a. test engine in operation. Of the catalyticeffects, those due to soluble iron are the most important. They areempirically duplicated by the addition of a soluble iron salt. Those dueto lead-bromide are duplicated by its addition.

The test was correlated with a slightly modified version of the L-4Chevrolet test. This modification comprised reducing the oil additionsfrom the 4 quarts in the usual procedure to 2 quarts, by reducing theusual 1 pint oil additions which are made at 4 hour intervals to pintadditions. This modification increases the severity of the test in itscorrosion and detergency components, particularly in the case of borderline oils.

For each test, the glass parts are cleaned by the usual chromic acidmethod, rinsed and dried. The metal parts are washed with chloroform andcarbon disulfide and polished with No. 925 emery cloth or steel wool. Anew copper-lead test piece is used for every test. The test piece ispolished before use, on a surface grinder to give it a smooth finish.The test piece is weighed before and after the test on an analyticalbalance t evaluate the corrosion. After placing the oil and corrosiontest unit in the tube, and bringing the assembly up to temperature inthe thermostat, soluble catalyst is added and the air flow is started.Lead bromide catalyst is added immediately after starting the air, andtiming of the test is begun.

The laboratory test conditions which were found to correlate with themodified Chevrolet procedure 36-hour test are the following:

At the close of the test period, the extent of corrosion is determinedby reweighing the corrosion test piece and determining the change inweight due to the test.

A sufficient volume of used oil is obtained from the test fordetermination of the usual used oil properties, such as pentaneinsolubles, viscosity increase, and neutralization number.

The data in the followin tables typify the results obtained in 10-hourSohio corrosion tests on conventional solvent extracted Mid-Continentlubricating oil base stock (SAE 30) and blends thereof compounded inaccordance with the invention.

Additive of Example No None VII VIII IX. X XI Concentration of Additivein Percent by Weight (of I oil) 1.0 1.0 1.0 L 1.0 Corrosion of Cu-Pbmgms. weight loss of)- 3. 1 3; 9 5.0 13.4 8. 4 3. 2 Viscosity Increase(SUE). 426 88 146 410 131 162 Pentane Insolubles (in pe cent by weight)0. 54 0.06 0. 78' 0.65 0. 60 0'; 28 Acid Number 3. 3 0. 93 0. 54 2. 400. 78 1.35

TABLE E Additive of Example No None XII XIII XIV XV Concentration ofAdditive in Percent by Weight (of oil) 0 1.0 1.0 1.0 1.0 Corrosion Cu-Pb(in milligrams weight loss of) 23.1 2. 9 .3 4. 3 2. 3 Viscosity Increase(SUS) 426 175 92 80 108 Weight Percent Pentane Insolubles (in percent byweight) 0. 54 1. 81 0. 08 0.63 0. 34 Acid Number 3. 3 0. 98 1.30 0. 540. 90

pentasulfide with degras, or with polybutene 0 polymer, or with mixturesof degras and polybutene polymer, at 300 F. for two hours, usingproportions of reactants and obtaining products which analyze asfollows:

Example No "1 Parts of Beactants:

Dcgras 100 Polybutene of 780 molecular weight 100 Polybutene of 940molecular weight i 36 P235 Product Analysis:

' Per Cent P 1 Per Cent S X Example No XVI XIX XVII XVIII Parts ofReactants:

Degras Polybutene of 780 molecular weight Polybutene of 940 molecularweight Piss Product Analysis.

Per Cent P Per Cent S Example No XX XXI XXII XXIII Parts of reactants: A

Degras "-1 50 50 25 25 Polybutene of7780 molecular weight 50 50 75 7528L 15 25 20 Product Analys Percent 1. 61 3. 5 2. 52. 4. Percent. S 7.41 12. 9 7. 72 14 Example No XXIV XXV XXVI XXVII Parts ofReactants:

Degras 50 50 25 25 Polybutene of 940 molecular weight 50 50 75 75 Pass2O 25 20 25 Product Analysis:

Percent P 2. 6 2.84 2. 7 3. 41 Percent S 10. 12. 80 10. 9 12.0

procedure. The results given in the following Tables F, G, H and I aretypical.

TABLE I (GO-HOURS) Additive of Example No. and

Concentration thereof in 2%, 3 Percent by Weight Piston Skirt Rating 7.0 1. 5 a. 0 1. 0

Viscosity Increase (S 276 110 211 106 Demerit Rating- 3.13 0. 72 2. 48,O. 58

Corrosion of Cu bearing mctaldn mgms. wt. loss per hearinghali-shell)104. 1 70. 0 96. 0 62. 5

The blank oil (without additive) had a demerit rating of 18.56.

TABLE G (GO-HOURS) Additive of Example No. and 1 Concentration thereofin per- 3% 055% 3% cent by Weight 1.5% F XVIII 2.25% F XIX Piston SkirtRating 4. 0 1. 5 4. 0 1.0

Viscosity Increase (SUS) 143 253 Acid Number 1.75 1. 25 2. 5 1. 00'

Pentane Insolubles (111 percent by weight) 1. 5 O. 35 3. 5 0. 30

Demerit Rating l. 45 0. 68 2. l 0. 5G

Corrosion oi Cu-Pb bearing metal (in mgms. wt. loss per bearinghall-Shell) 143. 2 64. 0 14-5. 2 78. 3

These Tables F and G data also show the marked superiority of acidtreated base lubricating oil containing the additives of the invention,as compared to the same oil containing about the same total amount ofthe separately reacted materials C and one of D, E or F (the lattermixtures may beregarded as the sum of the separate effects of the twoadded agents). In. each combination, 1. e., XVI compared to C+D incorresponding proportions, XVII compared to C-l-E in correspondingproportions, XVIII compared to 6+5 in corresponding proportions, and XIXcompared to C-I-F in corresponding proportions, both corrosion anddemerit rating are greatly improved.

TABLE H (60 HOURS) 3% by Weight of Additive of Example N o XX XXI XXIIXXIII Piston Skirt Rating 3. 5 2.0 2.0 3.0 Viscosity Increase (SUS) 64110 54 97 Acid Number l. 50 1.75 2.0 2.0 Pentane Insolubles (in percentby Weight) 0.80 2.0 0. 80 4. Demerit Rating 1. 07 1. 0. 8S 1. 67Corrosion of Cu-Pb bearing metal (in mgms. wt. loss per bearinghall-shell) 216 216 81. 3 192. 4

These Table H data show that additives of the type of the abovediscussed XVI and XVII, but made with different proportions ofphosphorus pentasulfide, are advantageous.

TABLE I (60-HOURS) These Table I data show that additives of the type ofthe above discussed XVII and XIX, but made with different proportions ofphosphorus pentasulfide, are advantageous.

Example XXVIII Following the procedure of Example XVI, an additive isprepared by reacting a mixture of 50 parts of reduced motor polymer and50 parts of degras with 44 parts of P285. An 89.69% yield of the productis obtained.

To illustrate the value of the products of the invention as additivesfor extreme pressure lubricants, an SAE 90 gear oil blend, consisting of55 parts of a Mid-Continent acid treated lubricating oil base stock(#300 red oil) and 40 parts by weight of Mid-Continent bright stock(#1), and compounded blends thereof containing 5% by weight of anadditive were submitted to the standard Timken extreme pressure test.The following results are typical.

TABLE I 800 R. P. M. E. P. Lubricant Timken Test Oil alone l5# Oil plus5% A 251; Oil plus 5% C 30# Oil plus 2.5% A, 2.5% C 2t# Oil plus 5%XXVIII 50?? These Table J data show the marked superiority of gear oilcontaining a typical additive of the invention XXVIII, as compared tothe same oil containing about the same total amount of the separatelyreacted materials A and C (the latter mixture may be regarded as the sumof the separate effects of the two added agents), and also as comparedto the same amount .of either A or C. The compounded blend of theinvention shows a more than 3-fold improvement. over the oil blendalone. s

The above working examples and specific embodiments are for illustrativepurposes only, and are not intended as limitations of the invention. InView of the foregoing disclosures, the art will clearly understand theinvention in its broad aspects, including variations and modificationsthereof.

If desired, the additives of the invention may be used together withother oil addition agents, e. g.,"pour point depressants or filmstrength agents. In some instances, it is desirable to include in alubricating oil containing the additive an agent for improving theclarity of the oil, e. g., lecithin, lauryl alcohol, and the like, whichare known to the art. In order to prevent foaming of the oil containinga small proportion of the additive, it is desirable in some cases to adda very small amount of tetra-amyl silicate, an alkyl ortho carbonate,ortho formate or ortho acetate, or a polyalkylsilicone oil, forpreventing foaming upon bubbling of air through oil containing a fewpercent of the additive.

It is intended to claim the invention broadly, except as limited by thefollowing claims.

I claim:

1. A reaction product of about 15 to about 44 parts by weight ofphosphorus pentasulfide, about 25 to about parts by weight of an esterselected from the group consisting of hydrogenated sperm oil, babassuoil and degras, and about 25 to about 75 parts by weight of a polyolefinselected from the group consisting of polypropenes and polybuteneshaving a molecular weight within the range from about to about 940, andmixtures thereof, reacted together simultaneously at a temperature inthe range of about 250 to about 350 F. to produce an oil-dispersiblematerial suitable for improving the characteristics of a minerallubricating oil.

2. A reaction product in accordance with claim 1 in which the polyolefinis reduced motor polymer.

3. A reaction product in accordance with claim 1 in which the ester isdegras.

4. A reaction product in accordance with claim 1 in which the ester ishydrogenated sperm oil.

JOHN M. MUSSELMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,063,629 Salzberg Dec. 8, 19362,316,082 Loane Apr. 6, 1943 2,343,831 Osborne Mar. 7, 1944 2,365,938Cook et al. Dec. 26, 1944 2,373,094 Berger et al Apr. 10, 1945 2,381,377Angel et al Apr. 10, 1945 2,411,153 Fuller Nov. 19, 1946 2,415,837Musselman Feb. 18, 1947 2,422,206 Musselman June 17, 1947 2,461,961Buckman et a1 Feb. 15, 1949 2,483,571 Brennan Oct. 4, 1949 OTHERREFERENCES Lubricating Oil Additives-G. G. Pritzker- Reprinted fromTechnical Sec.-Natl. Petroleum NewsOct., Nov., and Dec, 1945-pgs. 17-23.

1. A REACTION PRODUCT OF ABOUT 15 TO ABOUT 44 PARTS BY WEIGHT OFPHOSPHORUS PENTASULFIDE, ABOUT 25 TO ABOUT 75 PARTS BY WEIGHT OF ANESTER SELECTED FROM THE GROUP CONSISTING OF HYDROGENATED SPERM OIL,BABASSU OIL AND DEGRAS, AND ABOUT 25 TO ABOUT 75 PARTS BY WEIGHT OF APOLYOLEFIN SELECTED FROM THE GROUP CONSISTING OF POLYPROPENES ANDPOLYBUTENES HAVING A MOLECULAR WEIGHT WITHIN THE RANGE FROM ABOUT 145 TOABOUT 940, AND MIXTURES THEREOF, REACTED TOGETHER SIMULTANEOUSLY AT ATEMPERATURE IN THE RANGE OF ABOUT 250 TO ABOUT 350* F. TO PRODUCE ANOIL-DISPERSIBLE MATERIAL SUITABLE FOR IMPROVING THE CHARACTERISTICS OF AMINERAL LUBRICATING OIL.